Subscribed. Mine has similar wear. I scored a new seat bottom cover on eBay for about $100, but haven't made time to fit it yet. The guy ordered it and it was the wrong part for his X5 (leather vs leatherette).
There's a YouTube video here for an E46; this guy is a bit of a hack sometimes, but this video isn't half bad.
https://www.youtube.com/watch?v=FSKXFNJur-M